Funds are requested to purchase a scanning electron microscope to facilitate the research of a core user group of 4 NIH grantees and an additional group of 3 investigators. The need for a high-resolution, reliable SEM instrument available to this growing department is described. The 7 investigators then describe their projected use of an SEM for their studies of cell-cell recognition, cell-shape changes during development, intestinal differentiation in organ culture, fungal-host interactions, pollen and spore identification, reptile ecology, and Drosophila embryogenesis.